Configuring the UDP Lite
• Information About UDP Lite, page 1 • Configuring UDP Lite Globally (GUI), page 2 • Configuring UDP Lite on AP (GUI), page 2 • Configuring the UDP Lite (CLI), page 2
Information About UDP Lite The CAPWAP functionality, in Release 8.0, spans both IPv4 and IPv6. CAPWAP changes span the Controller and the AP. An AP running older image, that is not IPv6 capable, can join an IPv6 capable controller provided it has an IPv4 address and download image and vice-versa. Implementation of IPv6 mandates complete payload checksum for User Datagram Protocol (UDP) which slows down the performance of the AP and the Controller. To minimize the performance impact, Controller and AP supports UDP Lite that mandates only a header checksum of the datagram, thereby avoiding checksum on the entire packet. Enabling UDP Lite enhances the packet processing time. UDP Lite protocol uses the IP Protocol ID 136 and uses the same CAPWAP port as used by UDP. Enabling UDP Lite would require the network firewall to allow protocol 136. Switching between UDP and UDP Lite causes the AP to disjoin and rejoin. UDP Lite is used for data traffic and UDP for control traffic. A controller with UDP Lite enabled on it can exchange messages with IPv6 enabled APs along with the existing APs that support only IPv4.
Note A dual stack controller responds to a discovery request with both the IPv4 and IPv6 AP Managers. AP Discovery mechanism uses both, IPv4 and IPv6 addresses assigned to an AP. An AP will use the source address selection to determine the address to use to reach an IPv6 controller.
Cisco Wireless Controller Configuration Guide, Release 8.2 1 Configuring the UDP Lite Configuring UDP Lite Globally (GUI)
Configuring UDP Lite Globally (GUI)
Step 1 Choose Wireless > Access Points > Global Configuration to open the Global Configuration page. Step 2 Under the Global UDP Lite section, select the UDP Lite checkbox to enable UDP Lite globally. Note IPv6 UDP Lite is not applicable for APs connected with CAPWAPv4 tunnel. They are applicable only for APs joining the controller using CAPWAPv6 tunnel. Step 3 Click Apply to set the global UDP Lite configuration. Step 4 If desired, you can choose to override the global UDP Lite configuration by unselecting the Global IPv6 UDP Lite mentioned in Step 2. Note Switching between UDP and UDP Lite causes the AP to disjoin and rejoin.
Step 5 Click Save Configuration to save your changes.
Configuring UDP Lite on AP (GUI)
Step 1 Choose Wireless > Access Points > All APs to open the All APs page. Step 2 Select an AP Name with an IPv6 address and click on it to open the Details page of the selected AP. Step 3 Under the Advanced tab, select the UDP Lite checkbox to enable UDP Lite for the selected AP. Note This field is displayed only for APs that have joined the controller over CAPWAPv6 tunnel. The Web UI page does not display this field for APs joining the controller over the CAPWAPv4 tunnel . Step 4 Click Apply to commit your changes. Step 5 Click Save Configuration to save your changes.
Configuring the UDP Lite (CLI)
Step 1 Use this command to enable UDP Lite globally. config ipv6 capwap udplite enable all Step 2 Use this command to enable UDP Lite on a selected AP. config ipv6 capwap udplite enable
Cisco Wireless Controller Configuration Guide, Release 8.2 2 Configuring the UDP Lite Configuring the UDP Lite (CLI)
show ipv6 summary (Cisco Controller) >show ipv6 summary
Global Config...... Disabled Reachable-lifetime value...... 300 Stale-lifetime value...... 86400 Down-lifetime value...... 30 RA Throttling...... Disabled RA Throttling allow at-least...... 1 RA Throttling allow at-most...... 1 RA Throttling max-through...... 10 RA Throttling throttle-period...... 600 RA Throttling interval-option...... passthrough NS Mulitcast CacheMiss Forwarding...... Disabled NA Mulitcast Forwarding...... Enabled IPv6 Capwap UDP Lite...... Enabled Operating System IPv6 state ...... Disabled
(Cisco Controller) >
Cisco Wireless Controller Configuration Guide, Release 8.2 3 Configuring the UDP Lite Configuring the UDP Lite (CLI)
Cisco Wireless Controller Configuration Guide, Release 8.2 4